To develop a new nano-drug delivery system, to improve bioavailability and reduce adverse effect of antiretroviral drugs for human immunodeficiency virus (HIV).

Nano-drug delivery system produced by awater-oil-water emulsion and solvent evaporation technique was prepared by mixing anti-viral drug: efavirenz (EFV), tenofovir (TDF) and lamivudine (LAM) (weight ratio of 2︰1︰1) with poly (lactic-co-glycolic acid) (PLGA) and PLGA-chitosan (PLGA-CS). The drug-loaded nanoparticles were characterized for their particle size, poly-dispersity index and ζ-potential. The drug loading, encapsulation efficiency and drug release of PLGA and PLGA-CS nanoparticles were analyzed by high-performance liquid chromatography (HPLC). In vitro, cell viability was performed to evaluate biocompatibility and cytotoxicity.

Both PLGA-CS and PLGA nanoparticles exhibit good uniformity in particle size. Due to be coated with CS, the particle size of PLGA-CS nanoparticle was increased from (198.2 ± 2.3) nm to (219.8 ± 6.5) nm; the ζ-potential was increased from (-25.0 ± 1.6) mV to (23.5 ± 1.9) mV; drug encapsulation efficiency was increased from 49%-52% to 68%-77%. After a 2-month storage at 4 ℃ or 25 ℃, the drug retention of PLGA-CS nanoparticles remained above 90%. These results confirmed the excellent stability of PLGA-CS nanoparticles. The initial burst release of the antiretroviral drug from PLGA-CS nanoparticles exhibited a significant reduction, with the drug release remaining below 20% within 24 hours. The results in vitro studies pointed to the prolonged antiviral activity of AR-PLGA-CS. The stability of PLGA-CS was better than PLGA. Regardless of the concentration of PLGA-CS nanoparticles, the MTT assay showed that the cell viability was higher than 90%. This result indicated that PLGA-CS nanoparticles have low toxicity and excellent biocompatibility.

PLGA-CS nanoparticles exhibited high drug encapsulation efficiency, excellent stability, and the capacity of sustained drug release and enhanced therapeutic efficacy. This provides a new way for the clinical administration of antiretroviral drugs to patients with HIV infection.